Stirrups are well known in the prior art and have been used for hundreds of years. In general, a stirrup includes a D-shaped metal structure with a slot located in the center of the arcuate portion of the D-shaped structure for attachment of a stirrup strap, which in turn connects to a saddle. In use, the rider's foot is inserted into the D-shaped structure and the straight, base portion known as a footplate is located adjacent the sole of the rider's boot while the arcuate portion of the stirrup is located adjacent the upper of the rider's boot.
One of the problems associated with stirrups of the prior art is that if the rider is dismounted or thrown, they may not have sufficient time to withdraw their foot from the stirrup. Often the D-shaped structure fits firmly around the rider's boot, trapping the rider's foot. If the foot remains trapped in the stirrup, and the horse continues moving, the rider can be dragged along, often causing serious injury or death. Each year many people are injured or killed in this type of accident.
In order to overcome this well known problem, attempts have been made to provide safety stirrups that release the rider's foot if the rider is dismounted or thrown from the horse. One form of safety stirrup of the prior art includes a frangible or weakened portion adjacent the point where the stirrup is attached to the stirrup strap. If the rider is dismounted or thrown and their foot remains caught in the stirrup, the frangible portion breaks, releasing the stirrup from the stirrup strap. However this type of safety stirrup suffers from the drawback that it may break away from the stirrup strap during particularly hard riding, leaving the rider unbalanced, and unable to control the horse using his or her feet. Furthermore, the rider cannot re-mount until a new stirrup is fitted, which can be difficult or inconvenient if the stirrup breaks away in an isolated area. Furthermore, the frangible stirrup does not prevent leg injuries and is therefore of limited value for novice or disabled riders. A further disadvantage is that these stirrups are very bulky in the region where they attach to the stirrup strap and the increased bulk often causes excessive wear to the rider's clothing.
Another type of safety stirrup is disclosed in EP-0 065 714. This safety stirrup comprises a U-shaped release member supported at either end of the U within a D-shaped mounting member. During normal riding, the D-shaped mounting member and the U-shaped release member lie in the same plane. During normal riding, the sole of the rider's boot rests against the flat portion, or footplate, of the D-shaped member. If the rider is dismounted, the rider's foot causes the U-shaped release member to pivot out of the plane of the stirrup, concomitantly causing the footplate of the D-shaped mounting member to release at one end while the other end pivots away from the rest of the D-shaped mounting member. This allows the rider's foot to be released from the stirrup.
Other safety stirrups are described in AU-39229/95, U.S. Pat. No. 341,987 and DE-2003387. These safety stirrups also include articulated members that separate and release the rider's foot if the rider is dismounted or thrown. They all rely on forward or alternatively, backwards motion of the rider's foot as the rider is dismounted. However they are not specifically designed to release if the rider's foot moves upwards as he or she is dismounted, a common occurrence, particularly if the horse is bucking or jumping.
Another, quite different type of safety stirrup is described in U.S. Pat. No. 1,276,819. The stirrup comprises a pair of hingedly engaged, downwardly extending arms forming a U-shaped member, with the footplate hingedly engaged adjacent the end of one of the arms and releasably engaged adjacent the end of the other arm. The stirrup further comprises a vertically slideable plate, which in use rests against the upper of the rider's boot. If the rider's foot moves upwards, out of the normal in-use position, the plate slides upwards, activating a mechanism which causes one end of the footplate to release from one arm of the U-shaped member, thus releasing the rider's boot.
Yet another type of safety stirrup is disclosed in U.S. Pat. No. 1,321,653. This safety stirrup comprises a U-shaped mounting member having resilient, upturned arms that deform in response to strain. In this case, the foot support member has a lug portion that prevents it from upward movement, thus if the rider falls or is otherwise dismounted, the abnormal strain imposed on the stirrup causes the foot rest to disengage its keeper, the resilient arms of the U-shaped member deforming from the normal use position so that the foot rest can completely disengage from the arms.
Most safety stirrups can be classed as “one-way” release or “two-way” release stirrups. The “one-way” stirrup requires that the rider's foot be inserted in the stirrup in one particular direction or from one particular side if the release mechanism is to operate properly. Pressure exerted in the forward direction, that is, towards the rider's toe, will not cause the safety stirrup to release. Only pressure exerted in the rearward direction, that is, towards the rider's heel will cause the safety stirrup to release. Because the stirrup only opens up in one way or one direction, it is important that the rider's foot is inserted from the correct side of the stirrup, otherwise the release mechanism will not operate properly.
Conversely a “two-way” safety stirrup will release if pressure is exerted from either the forward or rearwards direction, hence the rider can place their foot in a two-way stirrup from either direction. For example a typical one-way safety stirrup is disclosed in AU-62109/90.
The safety stirrup of AU-62109/90 holds the rider's foot in a restraint that separates when the restraint is pivoted out of the normal position. International application PCT/AU97/00398 discloses another one-way safety stirrup. The safety stirrup of PCT/AU97/00398 also comprises a restraining means pivotally mounted between two extremities of an inverted U-shaped mounting means.
As mentioned above, when attached correctly to stirrup straps, the one way stirrups of the prior art release and open up only if the rider's foot pivots rearwards. Because they only open in the rearwards direction, they cannot open up if the rider's foot pivots forwards or pushes hard into the stirrup, as may occur as a result of very hard riding such as during a polo match or rodeo riding. While the one-way stirrup works well for all standards of riding including very hard riding, one-way stirrups of the prior art suffer from the disadvantage that they do not open up in response to certain types of riding accidents.
For example, a one way stirrup will not release if the rider's foot exerts strong forward pressure as the rider is thrown over the head of the horse, or to the side of the horse or in the course of jumping. Another problem with some designs of one-way stirrup of the prior art is that the rider's foot may still be retained within the U-shaped mounting means even when the restraint is pivoted out of the normal position and separates. Furthermore, as already mentioned, the correct operation of one-way stirrups is conditional on the stirrup being connected to the stirrup strap in one specific orientation, such that the rider's boot is inserted only in one particular direction into the stirrup. If the stirrup is oriented in the wrong direction it can release unexpectedly and lead to rider injury and/or loss of control of the horse. There is a risk that some riders, in particular novice riders, may unwittingly connect a one-way stirrup to the stirrup strap in the wrong orientation.
For these reasons, many riders prefer two-way stirrups. An example of a two-way safety stirrup of the prior art is disclosed in AU-26089/95. AU-26089/95 discloses a stirrup in which the rider's boot is held in a D-shaped restraint means which is pivotally mounted between two extremities of an inverted U-shaped mounting means. If the rider is dismounted from the horse, the restraint means pivots out of the normal position, one of the pivotal mountings releases from the mounting member, and the restraint means separates, thus releasing the foot from both the restraint and the inverted U-shaped mounting means.
One of the disadvantages of two-way stirrups of the prior art is that the restraint means can be pushed out of the normal position by the movement and pressure exerted by hard riding. The amount of forward pressure required to cause the safety stirrup to release is approximately the same as the amount of rearward pressure required to cause release. Professional riders such as jockeys, mountain cattlemen, rodeo riders, polo players and the like exert enormous pressure on stirrups as they pull up a horse or lean back to resist being thrown over the horse's head. The pressure of the rider's foot being pressed hard into the stirrup can cause a two-way stirrup to suddenly release, unbalancing the rider and potentially causing them to fall from the horse.
Typically, the safety stirrups of the prior art also have the disadvantages of being made of metal, and thus being relatively heavy, and of having relatively complicated construction. In general, the stirrups of the prior art comprise articulated members or complicated joints between members which separate when the rider is dismounted—the articulation and complicated construction contributing to the cost of construction.